Intel PXA255 DMA Target Address Registers DTADRx, DSADRx Bit Definitions, Source Address, Srcaddr

Models: PXA255

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DMA Controller

Table 5-10. DSADRx Bit Definitions

 

 

 

 

0x4000_02x4

 

 

 

 

DMA Source Addr Register

 

 

 

 

 

DMA Controller

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(DSADRx)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SOURCE ADDRESS

 

 

 

 

 

 

 

 

 

 

 

 

reserved

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reset

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Uninitialized

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bits

 

 

Name

 

 

 

 

 

 

 

 

 

 

 

Description

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Source Address (read / write).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

31:3

 

SRCADDR

Address of the internal peripheral or address of a memory location.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Address of a memory location for companion -chip transfer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Source Address Bit 2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2

 

SRCADDR

Reserved if DSADR.SrcAddr is an external memory location

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Not reserved if DSADR.SrcAddr is an internal peripheral (read / write).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1:0

 

 

 

reserved

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5.3.6DMA Target Address Registers (DTADRx)

To software, DTADRx (Table 5-11) is read only in the Descriptor Fetch Mode and is read/write in the No-Descriptor Fetch Mode.

These registers contain the target address for the current descriptor in a channel. The target address is the address of an internal peripheral or a memory location. On power up, the bits in this register are undefined. If the target address is the address of a companion chip or external peripheral, the target address must be aligned to an 8-byte boundary. This allows bits [2:0] of the address to be reserved. If the target address is the address for an internal peripheral, the address must be 32-bit aligned so that bits [1:0] are reserved. DTADRx must not contain the address of any other internal DMA, LCD, or MEMC register.

The DTADRx must not contain a flash address because writes to flash from the DMAC are not supported.

This is a read/write register. Ignore reads from reserved bits. Write zeros to reserved bits.

5-22

Intel® PXA255 Processor Developer’s Manual

Page 172
Image 172
Intel PXA255 manual DMA Target Address Registers DTADRx, DSADRx Bit Definitions, Source Address, Srcaddr